Ace Comics was the banner under which pulp magazine publisher Aaron A. Wyn and his wife Rose Wyn produced comic books between 1940 and the end of 1956. The Wyns had been publishing pulp fiction under the Periodical House and Magazine Publishers names since 1928. Like many comic book publishers of the day, Ace Comics earlier series included costumed superheroes, although as trends in the comic book market changed by the 1950s the focus shifted more to other genres, such as crime, horror, romance, and later, Westerns.
Their most successful, and longest-running, superhero title was Super-Mystery Comics featuring Magno the Magnetic Man and his boy partner Davey, who appeared in 28 issues of the title's 48-issue run. Horror titles included Baffling Mysteries, Hand of Fate and Web of Mystery, while their contribution to the crime comics genre was Crime Must Pay the Penalty (the title later shortened to Penalty for the final two issues).